Drill



Juk 1 1924.

P. STEFANICH DRILL Filed Nov. 16, 1922 2 Sheets-Sheet 2 Will!!! Q111L111 /////Ax rn'r s'rnrcn, or INDIANA e v jlltlt IANA, essrcn'on. orone-new 'ro t STEFANICH, or rnnrann i 1:.

To all whom it may concern:

Be it blown that l, PETER STEFANICH, a citizen of Austria, residin atIndiana Harbor, in the county of La e and State of llndiana, haveinvented certain new and useful Improvements in Drills; and l do declarethe followin to be a full, clear, and exact description oi theinvention, such as will enable others skilled in the art to which itappertains to make and use the same.

T is invention relates to a drill, the general obj ect of the inventionbeing to provide means for boring a square hole by means of a centralbit and four side cutters which cut the corners from the walls of thehole made by the bit.

Another object of the invention is to provide means for permitting thepart which carries the cutters to have vertical or longitudinalmovement. 4

The invention also consists in certain other features of constructionand in the combination and arrangement. of the several parts, to behereinafter fully described, illustrated in the accompanying drawingsand specifically pointed out in the appended claims.

"lln describing my invention in detail, reference will be had to theaccompanymg drawings wherein like characters denote like orcorresponding parts throughout the several views, and in which V Figure1 is an elevation of the invention.

Figure 2 is an elevation, with parts in section, of the drill carryingmember.

Figure-3 is a section on line 33 of Figure 1.

Figure t is a view'of the drill bit.

Figure 5 is a view of one of the guide bar supporting clamps.

Figures 6 and 7 are views showing one of the saw-carrying shafts in sideelevation.

Fi ure 8 is a view showing the saw-carryin s aft in end elevation.

11 these views, 1 indicates the drill press having a chuck to which theshank of the bit 2 is connected so that the bit can be rotated in theordinary manner and made to travel towards and away from the work. Asectionalucollar 3 is secured tosaid press and carries s uare sockets 4for the guide rods 6,'the rods being secured in the sockets by setscrews 7. The shank of the bit passes Application filed November it,1922. serial no. 601,40fi.

through a cylindrical body 8, the bit and shank being rotatablyconnected with the body, preferably by a ball bearing 9 placedbetween'the lower end of the body and the head of the bit and anotherball bearing 10 placed between the upper end of the body and the washer11, the washer being held in place by the nut 12 which engages a screwthreaded part of the shank and is secured by the lock nut 13. The washermay be held rotatably in relation to the shank by the flat part 14, thewasher having a similar flat portion. The body 8 has secured thereon thesectional collar 15 which carries the sockets 16 for slidably receivingthe rods 6, so that the body is guided in its vertical movement by saidrods and is held against rotary movement. The,

bore of the body. has an enlarged part at its lower end to receive anenlarged part of the shank, this part of the shank having a bevel gear17 formed thereon. Smallshafts 18 are mounted in the lower part of the'body, the inner ends of these shafts carrying the bevel gears 19 whichmesh with the gear 17 so that the shafts are revolved when the drill andits shank are rotated. The outer ends of the shafts have secured theretothe circular cutters 20, which are made somewhat similar to a saw, theseoutters being so arranged that they will cut the corners from the wallof the hole made by the bit so that the device will make a square hole.The upper part of the body is formed with the oil holes 21 so that the 5movable parts may be provided with lubricant.

From the foregoing it will be seen that when the bit is rotated from thepress and tltt advanced into the Work, the cutters will llltl makechanges in the construction and in the combination and arrangement ofthe several parts, provided that such changes fa]! Within the scope ofthe appended claims.

I claim: A

1. In combination with a .drill, a chuck for drivin the drill, and astationary member towar and from which said chuck-is a movable; anelongated casing through Which said drill passes, means connecting c thedrill and casing for axial movement as having diametrically opposedexternal sockets, a pair of parallel guide rods at the exterior of saidcasing and chuck rigidly held at one end in said sockets, a secondcollar clamped around said casing, and diametrically opposed externalsockets carried by said second collar and slidably surrounding saidguide rods.

2. A structure. as specified in claim 1; each of said collars comprisinga main semi-circular section whose ends carry the sockets, an auxiliaryselm circular section, and fasteners connecting the ends of saidsections.

In testimony whereof I have hereunto affixed mysignature.

PETER STEFANICH.

